Twenty-One Days, Not Ninety: How Long Dual Antiplatelet Therapy Should Actually Run After a Minor Stroke
A high-risk TIA is exactly the population two major trials built the case for short-course dual antiplatelet therapy around — the disagreement isn't whether to start it, but how long a habit borrowed from cardiology practice should be allowed to run before the bleeding risk catches up with the benefit.
V.N., a 55-year-old woman who manages a busy dental office and prides herself on never missing a day, noticed her right hand "just stopped working" for about fifteen minutes while filing patient charts on a Tuesday afternoon — no speech trouble, no facial droop that she or her staff noticed, and it resolved completely before she'd even finished deciding whether to call anyone. She almost went home. A coworker who has a father with stroke history talked her into the emergency department instead, arriving about ninety minutes after the episode resolved. She has hypertension, treated with lisinopril, and no history of prior stroke, TIA, or bleeding.
Her exam on arrival is entirely normal. Her ABCD2 score comes out to 4 — one point for a triage blood pressure of 148/90, two for a unilateral motor deficit, one for a duration between ten and sixty minutes, and nothing for age, since the score's threshold is 60 and she is 55, or for diabetes, which she doesn't have. Four is the moderate band, not the high-risk one, and that is worth saying out loud precisely because the number is often reported as though it were the whole risk assessment. What actually settles her risk category is the imaging: MRI shows a tiny punctate diffusion restriction in the left corona radiata, small enough to have left no deficit but sufficient to make this a completed minor ischemic stroke rather than a transient attack — a distinction that moves her out of the score's population entirely and into the one the antiplatelet trials enrolled directly. CHANCE and POINT, the two major trials establishing short-course dual antiplatelet therapy in exactly this population, both randomized clopidogrel plus aspirin against aspirin alone in minor stroke and high-risk TIA and found reduced recurrent stroke with the combination — POINT's own trial ran the comparison out to ninety days, but its prespecified day-by-day analysis showed the ischemic benefit was concentrated in roughly the first three weeks, while major hemorrhage risk kept climbing steadily across the full ninety-day period the drug was actually given. The question in front of the team isn't whether to start dual therapy — her risk profile makes that straightforward — it's how long to keep her on it before that crossover point works against her instead of for her.
In the stroke unit, planning the antiplatelet course
Clopidogrel plus aspirin for twenty-one days, then drop to aspirin alone. Her ABCD2 is 4, which is moderate rather than high — but the score is beside the point once the MRI shows a real infarct. CHANCE and POINT both enrolled minor ischemic stroke as well as high-risk TIA, and her confirmed DWI lesion puts her squarely in that first group regardless of what the score says. But POINT's own prespecified day-by-day analysis is worth naming specifically: the ischemic benefit of dual therapy was front-loaded in roughly the first three weeks, while major hemorrhage kept accumulating in a straight line across the full ninety days the trial tested. The crossover happens well before day 90.
I'll ask the obvious question from where I sit: in coronary practice, a recently symptomatic vascular territory generally gets sustained dual therapy for months, not weeks, because the vessel stays vulnerable. Why wouldn't the same general principle apply here — longer coverage for a vessel that just had an event?
Because the thing driving your coronary practice doesn't have an analogue here. A stented artery carries an ongoing mechanical thrombosis risk from the stent itself for as long as it takes to fully endothelialize — that's a persistent, months-long trigger. A minor stroke or TIA has no equivalent ongoing mechanical process; the excess ischemic risk POINT measured was concentrated early and didn't keep recurring the way stent thrombosis risk does.
That's not a rejection of your instinct, it's a reason the specific mechanism doesn't transfer across vascular territories the way it might seem like it should. Twenty-one days, then aspirin alone, matches what the actual data for this condition supports.
Agreed: clopidogrel 75mg daily plus aspirin 81mg daily for 21 days, then discontinue clopidogrel and continue aspirin monotherapy indefinitely. Blood pressure management with her existing lisinopril was reinforced as part of the same visit, and she was scheduled for outpatient follow-up within two weeks.
Not agreed, and left open rather than resolved: whether CYP2C19 genotype should be checked before committing to clopidogrel-based dual therapy in patients like her, the same question a different pivot in this same case set addresses more directly — raised here, not settled here.